ANT Forum

I have a project which requires tracking an object from it's host in 1-dimension at a range of 1.5ft to 60ft, or up to 100ft, with an accuracy goal of 1mm. Direct line of sight is available. The application will be indoors. I would like to potentially run up to 1000 (one-thousand) pairs of these devices without interfering with each other.

A friend tipped me off that Ant may be the solution to my problem.

I'm thinking the system would work by sending a signal from the host to the mobile object, recording the sending time. Then having the mobile object respond to the signal, and send back to the host, where the host would record the time, and derive from the distance the Time-of-Flight.

Is Ant capable of doing what I am asking it to? Thanks.      

Hi,

At this time I wouldn't advise it. While it is physically possible to do time of flight using ANT, the biggest issue is the resolution and precision required to make usable timing measurements for distance estimation (not to mention other issues such as multipath). In order to make usable measurements for distance, you would require nanoseconds of resolution as light can travel ~1ft/ns.

ANT devices are based on a 32.768 kHz timing source, so the resolution for timing is down to 1 tick or ~30.5us, which would make the resolution equal to tens of thousands of feet. Even the 64 MHz system clock on an nRF52 SoC ticks at 15.6ns which would be too slow to run a timer for nanosecond resolution.

Cheers